Liquid detergent products are often considered to be more convenient to use than are dry powdered or particulate detergent products. Liquid detergents have therefore found substantial favor with consumers. Such liquid detergent products are readily measurable, speedily dissolved in the wash water, capable of being easily applied in concentrated solutions or dispersions to soiled areas on garments to be laundered and are non dusting. They also usually occupy less storage space than granular products. Additionally, liquid detergents may have incorporated in their formulations materials which could not withstand drying operations without deterioration, which operations are often employed in the manufacture of particulate or granular detergent products.
Liquid detergent products in terms of their most basic components will generally essentially comprise functional ingredients such as one or more surface active agents (surfactants) that promote and facilitate the removal of stains and soils from fabrics laundered in aqueous wash solutions formed from such liquid detergent products. Liquid detergent products will also generally contain a liquid carder such as water which serves to dissolve or at least suspend the essential functional surfactant ingredients.
In addition to surfactants and a carrier liquid, heavy duty liquid detergent products can also contain a wide variety of additional functional ingredients which serve to boost the fabric cleaning effectiveness of the products into which they are incorporated. Such additional functional ingredients can include, for example, various detergent builders, chelating agents, bleaching agents, bleach activators or catalysts, detergent enzymes, enzyme stabilizers, grease/oil solvents, dye transfer inhibition agents, pH controllers, brighteners and the like. While such additional composition components can enhance composition cleaning performance, such additional functional materials can also be relatively expensive, thereby driving up the cost of manufacture of such products and ultimately driving up the cost of such products to the consumer.
Liquid detergent products may also contain other types of additional ingredients which do not necessarily enhance the cleaning performance of such products but which may be useful for improving the physical stability or the aesthetics of such products. Such non-functional ingredients include a wide variety of materials such as hydrotropes, additional solvents, phase stabilizers, thickeners, suds suppressors, perfumes, dyes and the like. Again, while such non-functional ingredients can beneficially affect the stability or appearance of detergent products containing them, such non-functional ingredients also add cost to the product without necessarily serving to improve the fabric cleaning performance thereof.
Given the foregoing considerations, it is highly desirable when formulating liquid detergent products to arrive at a proper balance of such competing factors as composition cost, composition cleaning performance and composition stability or aesthetics. There remains a continuing need to identify heavy duty liquid laundry detergents with ingredients selected to provide suitably effective stain/soil removal from fabrics laundered therewith while at the same time minimizing the cost of such products. Accordingly, it is an object of the present invention to formulate heavy duty liquid laundry detergent compositions containing a selected cost effective surfactant system combined with relatively high concentrations of the most cost effective liquid detergent carrier--water.
It is a further object of the present invention to provide such liquid detergent compositions containing only minimal amounts of additional, relatively costly functional cleaning performance-enhancing ingredients.
It is the further object of the present invention to provide such liquid detergent compositions which also contain only minimal amounts of additional, relatively costly non-functional stability- or aesthetics-enhancing ingredients.